The poll, taken Aug. 22, represents a dramatic reversal of fortune for Congressman Akin, who sparked national controversy Sunday with a comment about rape and pregnancy in an interview with a St. Louis TV station. Akin, who opposes abortion without exceptions, asserted that women’s bodies have the ability to prevent pregnancy during a “legitimate rape."

Before the interview, Akin led McCaskill by an average 5 percentage points, according to RealClearPolitics. She was seen as the most vulnerable incumbent Democrat this cycle. Beating her was key to the Republicans’ goal of retaking control of the Senate, where 53 members currently caucus with the Democrats, versus 47 Republicans.

Most Missouri Republicans want Akin to drop out of the race, while most Democrats want him to stay, according to Rasmussen. Overall, 41 percent of likely Missouri voters say “stay” and 42 percent say “go.”

Akin apologized later on Sunday for what he called an “ill-conceived” remark, but the damage was done. Top Republicans, from Mitt Romney on down, pleaded with Akin to drop out. Republican Party committees and outside groups have also cut off funding to Akin, and it remains to be seen if he can raise enough money on his own to stay in the race. If he drops out by Sept. 25, Republicans can replace his name on the ballot, though a court order would be needed.

The fact that McCaskill remains under 50 percent in both her race against Akin and in her favorability numbers (48 percent favorable, 48 percent unfavorable) shows that she’s still beatable, but in all likelihood, only with a different Republican on the ballot.

Missouri voters see McCaskill as closely tied to President Obama, who is unpopular in a state that has been trending Republican for years.